When sampling an audio signal for digital transmission, a sample rate is determined by a clock, typically embodied as a quartz crystal oscillator, the output frequency of which can differ from a desired nominal rate for multiple reasons. In telecommunications systems where network access devices have independent clocks, data rate mismatches between two clock rates will inevitably occur. Such differences cause artifacts in an audio signal when it is reconstructed from digital samples. Those artifacts can be manifested as clicks, pops and/or momentary silence, all of which are annoying.
A prior art “brute force” method of simply adding or removing zero samples or repeat samples from a digital signal does not solve the problems created by dissimilar clocks. Adding or removing samples will instead introduce discontinuity in an audio signal and generate audible artifacts (clicks or pops) that will deteriorate the end user experience. Introducing average sample of the surrounding samples still doesn't resolve the audible artifacts completely.
Another prior art method of predicting samples based on historical data may become too much computationally expensive for embedded type applications.
A simple, computationally efficient method of matching different digital sample transmission rates would be an improvement over the prior art.